Correlation of Forces and Conservation of Energy

Sometime around 1800 there came over the European mind a shadow of unease about Newtonian science. Beauty, life, and mystery were all expiring in a desert of atoms and forces and soulless mechanisms—so the poets held, but not only they. Science also, many people felt, must seek higher themes, broader principles, deeper foundations—symmetries, connections, structures, polarities, beyond, across, and above particular findings. Elusive, obscure, sometimes merely obscurantist, remarkably this inchoate longing actualized itself in a few decades in a succession of luminous discoveries, and flowed forward into the idea of energy.

In Germany it took shape in a much-praised, much-derided movement, interminable in discourse about Urprinciples and life forces, spearheaded by Lorenz Oken and Friedrich Schelling under the name Naturphilosophie, turgid indeed, but source of a powerful new credo. Nature is one, and so...